Aircraft such as the B-17E (not available to Perl harbour) or more Likely Avro Lancaster or Halifax (first service Jan 1941) would have been very usefull to the Germans as maritime reconaisance bombers. For instance I'd assert that a squadron of lancaster/halifax equivalanet bombers orbiting above the Bismark would have spoiled the King George V, Nelson and Rodney's attack on the Bismark and have given the Germans enough time to concentrate u-boats in the area. The fleet air arms Fairy Fulmars and Swordfish would be useless against that kind of aircraft.
The He 177 would take nearly another 2 years to get to a decent level of opperational reliabillity when it was ready it did rather well in attacking Soviet factories, performing some remarkable missions using Fritz-X bombs that severely disrupted Soviet Iron and Steal making. I agree that they would be useless attacking tactical targets such as concentrations of armour. However they would be make life very difficult due to their abillity to strike at targets all over the soviet union and UK and the effectiveness of guided weapons such as Hs 293 and Fritz-X. Rather than the big, highly tooled but inflexible production runs of US and British bombers I see a 4 engined He 177 entering service in Jan 1941 with DB601 engines and perhaps 800 year being produced with progressive upgrades to the point the machine turns into a 360-400mph machine powered by 4 x DB603 engines by 1944 thus remaining a difficult target for allied fighters.
I like to make the analogy of a situation in which the Germans are given 500 crewed B-29's and a production of 100 aircraft per month for free in 1944. I would say that they would all be shot down within a few months by aircraft such as the P-47D-25, P-38L, Spitfire XIV and likely Spitfire VII and Mustang P-51D or Mosquito night fighters. The allies had that many high performance aircraft and pilots they would nullify 500 B-29's in short order. What was a B-29's rear armanent going to do to a P-47? A German 4 engined bomber has to be fast and advanced and used carefully. No massed carpet bombing raids that would lead to attrition.
As far as getting a German jet engine in production 1 year early, it's possible, I think but requires a considerable rethink and change in mentality.
The Germans didn't have an alloy as good as nimonic (80% nickel 20% Chromium) and used tinidur for the jumo 004A as well as the production jumo 004B1 as far as I can tell. However the Jumo 004A engine WAS considerably more durable than the latter production versions which reflected the wider usage of this alloy in the engine as well as the higher grade fabrication by reliable skilled personel; I think kay quotes abpout 100 hours, which is more than the 50 hours of J-37 of the early P-80. The latter Jumo 004B1 used tinidur only for the gas turbine blades and the inlet guide vances. The combustion chamber cans, injector nozzles, exhaust duct, exhaust cone were all mild carbon steel and these areas caused considerable problems in reliabillity rather than just the turbine.
Also noteworthy is the fact that the German engine was almost completed stamped out of sheet metal, even the turbine, to save not only on refratroy alloys but man hours as well. AFAIKT the turbine blades of the Whittle engines were carefully machined. The attachment points were a fir tree root that distributed stresses whereas the jumo used a hoop and pin attachment that was silver soldered. The HeS 011 had the blades loose to allow movement in the manner of many modern compressors.
So its clear a different mentality was at work with enornous effort in the German camp to save material and man hours according to the Speer/Sauer directives but that this cost reliabillity and initial service entry.
Now its worth looking at the Heinkel Hirth HeS 008 which was in many ways the opposit of the Jumo 004. This engine had the same thrust but less than half the weight with parameters in terms of thrust to weight ratio, frontal area per unit thrust ratio and fuel efficiency unbeaten till 1947. It was running in 1942.
The HeS 008 was designed by Max Adolf Mueller. Ingineer Mueller had started design of the Jumo 002 at Junker airframe division however the RLM muscled in as it didn't think aiframe makers should be designing engines (even though the engine makers weren't interested) and they put the Austrian turbocharger expert Franz Anselm in charge of a program that became the Jumo 004 at the Junkers engine division. This left Mueller out of a job, so he moved over the Heinkel. Heinkel had the same problems with the RLM but Ernest Heinkel had got around it by purchasing the engine manufacturer Hirth.
The HeS (essentially the jumo 002) took a completely different approach;
1 the compressor was also axial however it was of the reaction type instead of impulse type. This made it over 10% more efficient and meant it required only 5 stages instead of 3 and so it was much shorter and lighter. The penalty was that the higher tollerances meant the blades needed some machining and the presence of axial thrust meant a thrust bearing needed to be added.
2 It used variable pitch turbine inlet nozzles.
My argument would be that by using a reaction style compressor (where the pressure is built over the stator as well as the rotor of the compressor) then the increased efficiency would have allowed a reduction in turbine inlet temperatures so as to make the hot section of the engine more reliable.
Other technical issues not really effectively addressed till 1945 were
1 The failure to develop accuate fuel control systems, a problem of allied engines as well. This is not a hard task: the compressor air mass flow has to be measured and fuel proportioned accordingly, there were many ways of achieving this and it was not worse than the fuel injection systems used in German piston engines. Overall control via centrifugal governor then trims this proportion of fuel while temperature sensors add a degree of protection. The primitve fuel control (centrifugal governor only) of the early Jumo tended to over dose fuel during engine acceleration and underdose at deaccerleration which lead to over temperatures and burnouts or flameouts as well as damaging engine life.
This, rather than alloys, I think was the main problem of the Jumo. However the tendancy to make things as simple as possible initially caused this preventable problem.
Duplex nozzles that switch to a seperate spray nozzle at low flow which is needed for stable flame combustion during idle and high altitudes also would have helped the engine, again scheduled at wars end.
The He 177 would take nearly another 2 years to get to a decent level of opperational reliabillity when it was ready it did rather well in attacking Soviet factories, performing some remarkable missions using Fritz-X bombs that severely disrupted Soviet Iron and Steal making. I agree that they would be useless attacking tactical targets such as concentrations of armour. However they would be make life very difficult due to their abillity to strike at targets all over the soviet union and UK and the effectiveness of guided weapons such as Hs 293 and Fritz-X. Rather than the big, highly tooled but inflexible production runs of US and British bombers I see a 4 engined He 177 entering service in Jan 1941 with DB601 engines and perhaps 800 year being produced with progressive upgrades to the point the machine turns into a 360-400mph machine powered by 4 x DB603 engines by 1944 thus remaining a difficult target for allied fighters.
I like to make the analogy of a situation in which the Germans are given 500 crewed B-29's and a production of 100 aircraft per month for free in 1944. I would say that they would all be shot down within a few months by aircraft such as the P-47D-25, P-38L, Spitfire XIV and likely Spitfire VII and Mustang P-51D or Mosquito night fighters. The allies had that many high performance aircraft and pilots they would nullify 500 B-29's in short order. What was a B-29's rear armanent going to do to a P-47? A German 4 engined bomber has to be fast and advanced and used carefully. No massed carpet bombing raids that would lead to attrition.
As far as getting a German jet engine in production 1 year early, it's possible, I think but requires a considerable rethink and change in mentality.
The Germans didn't have an alloy as good as nimonic (80% nickel 20% Chromium) and used tinidur for the jumo 004A as well as the production jumo 004B1 as far as I can tell. However the Jumo 004A engine WAS considerably more durable than the latter production versions which reflected the wider usage of this alloy in the engine as well as the higher grade fabrication by reliable skilled personel; I think kay quotes abpout 100 hours, which is more than the 50 hours of J-37 of the early P-80. The latter Jumo 004B1 used tinidur only for the gas turbine blades and the inlet guide vances. The combustion chamber cans, injector nozzles, exhaust duct, exhaust cone were all mild carbon steel and these areas caused considerable problems in reliabillity rather than just the turbine.
Also noteworthy is the fact that the German engine was almost completed stamped out of sheet metal, even the turbine, to save not only on refratroy alloys but man hours as well. AFAIKT the turbine blades of the Whittle engines were carefully machined. The attachment points were a fir tree root that distributed stresses whereas the jumo used a hoop and pin attachment that was silver soldered. The HeS 011 had the blades loose to allow movement in the manner of many modern compressors.
So its clear a different mentality was at work with enornous effort in the German camp to save material and man hours according to the Speer/Sauer directives but that this cost reliabillity and initial service entry.
Now its worth looking at the Heinkel Hirth HeS 008 which was in many ways the opposit of the Jumo 004. This engine had the same thrust but less than half the weight with parameters in terms of thrust to weight ratio, frontal area per unit thrust ratio and fuel efficiency unbeaten till 1947. It was running in 1942.
The HeS 008 was designed by Max Adolf Mueller. Ingineer Mueller had started design of the Jumo 002 at Junker airframe division however the RLM muscled in as it didn't think aiframe makers should be designing engines (even though the engine makers weren't interested) and they put the Austrian turbocharger expert Franz Anselm in charge of a program that became the Jumo 004 at the Junkers engine division. This left Mueller out of a job, so he moved over the Heinkel. Heinkel had the same problems with the RLM but Ernest Heinkel had got around it by purchasing the engine manufacturer Hirth.
The HeS (essentially the jumo 002) took a completely different approach;
1 the compressor was also axial however it was of the reaction type instead of impulse type. This made it over 10% more efficient and meant it required only 5 stages instead of 3 and so it was much shorter and lighter. The penalty was that the higher tollerances meant the blades needed some machining and the presence of axial thrust meant a thrust bearing needed to be added.
2 It used variable pitch turbine inlet nozzles.
My argument would be that by using a reaction style compressor (where the pressure is built over the stator as well as the rotor of the compressor) then the increased efficiency would have allowed a reduction in turbine inlet temperatures so as to make the hot section of the engine more reliable.
Other technical issues not really effectively addressed till 1945 were
1 The failure to develop accuate fuel control systems, a problem of allied engines as well. This is not a hard task: the compressor air mass flow has to be measured and fuel proportioned accordingly, there were many ways of achieving this and it was not worse than the fuel injection systems used in German piston engines. Overall control via centrifugal governor then trims this proportion of fuel while temperature sensors add a degree of protection. The primitve fuel control (centrifugal governor only) of the early Jumo tended to over dose fuel during engine acceleration and underdose at deaccerleration which lead to over temperatures and burnouts or flameouts as well as damaging engine life.
This, rather than alloys, I think was the main problem of the Jumo. However the tendancy to make things as simple as possible initially caused this preventable problem.
Duplex nozzles that switch to a seperate spray nozzle at low flow which is needed for stable flame combustion during idle and high altitudes also would have helped the engine, again scheduled at wars end.
